only install casc support plugin when needed (#14862)

The latest released version of the configuration
as code support plugin is 1.19 for newer versions
of the configuration as code plugin it's no longer
needed. Using semver compare to check for this condition.

Signed-off-by: Torsten Walter <mail@torstenwalter.de>

stable/jenkins/Chart.yaml

@@ -1,7 +1,7 @@
 apiVersion: v1
 name: jenkins
 home: https://jenkins.io/
-version: 1.2.2
+version: 1.3.0
 appVersion: lts
 description: Open source continuous integration server. It supports multiple SCM tools
   including CVS, Subversion and Git. It can execute Apache Ant and Apache Maven-based

stable/jenkins/templates/config.yaml

@@ -323,8 +323,10 @@ data:
   {{- if not (contains "configuration-as-code" (quote .Values.master.installPlugins)) }}
     configuration-as-code:{{ .Values.master.JCasC.pluginVersion }}
   {{- end }}
-  {{- if not (contains "configuration-as-code-support" (quote .Values.master.installPlugins)) }}
+  {{- if semverCompare "<=1.19" (printf "%v" .Values.master.JCasC.pluginVersion) }}
+    {{- if not (contains "configuration-as-code-support" (quote .Values.master.installPlugins)) }}
     configuration-as-code-support:{{ .Values.master.JCasC.supportPluginVersion }}
+    {{- end }}
   {{- end }}
 {{- end }}
 {{- end }}

stable/jenkins/values.yaml

@@ -194,8 +194,10 @@ master:
   # etc.  Best reference is https://<jenkins_url>/configuration-as-code/reference.  The example below creates a welcome message:
   JCasC:
     enabled: false
-    pluginVersion: 1.5
-    supportPluginVersion: 1.5
+    pluginVersion: 1.19
+    # it's only used when plugin version is <=1.18 for later version the
+    # configuration as code support plugin is no longer needed
+    supportPluginVersion: 1.19
     configScripts:
       welcome-message: |
         jenkins: